Switch for electric circuits.



I E. B. WEDMORE. SWITCH TCR ELECTRIC CIRCUITS. APPLICATICNTIIIIIII CCT. Ie. 190e.

Patented Apr. 6, 1909.

z SHEETS-SHEET 1.

E. B. WEDMORE.

SWITCH FOR ELECTRIC CIRCUITS.

' APPLICATION FILED OUT. 16, 1906. 91 7,209.. Patented Apr. 6, 1909.

2 SHEETS-SHBET 2.

Witnesses: /nv'entorv l 7i Edmund@ edmorfi-z;E by

y rietyf oflplaces,

ranged in an arc of a i .theseV contacts.

vso

after set forth andparticularly pointed out of this application.

f the preferred 'o'rmfof my device; Fig.-

"To au Siding at Rugby,`

` 'f This'inventionlrelates to switches for elec- 'vision of a simple and eiiicient device of this character in which the arrangement of cir- .fci'xits' may be varied in a convenient manner .and in which the contact resista-nce is rea construction in which the contacts for .tighten the contacts as it i trolling element will then 4 til theeoiitacts are loosened.

shown in DMND B. WEDMORE, or RUGBY, ENGLAND, A coRronATioN ASSIGORTO GENERALV ELECTRIC) COMPANY,

OF NEW YORK.

SWITCH FOR ELECTRIC CIRCUITS.

No. 917,209. Application filed October 16,

whom it may concern.'

. Be it known that I, EDMUND B. Wnniuonn, a subject ofthe King of GrreatJ Britain, re-

England, have invented certain new and useful Improvements in Switches for Electric Circuits, of which the following is a specidication.l f

tric circuits, and has for its object the produced to a minimum.

` My invention, While it is capable of a broad application and may be used in a vais particularly Well adapted for controlling the circuits of measuring instruments. In a device of this character, it is essentialthat the contact resistance shall be low so as not to interfere with the readings of the instrument. In carrying' out'my invention, I provide i My invention, therefore, consists in the features of construction and in they arrangen ment` and combination of elements hereinin the claims annexed to and forming a part In thedi'awings, in which I have shown forms of my invention, Figure 1 is an elevation partly in section of one 2 is a plan vien.T of.' the. same;vFig. 8 is a view similar to Fig. 1, offv a slightly modified form; and Fig. 4 is a detailoiFthe brush tightening mechanism Referring. to the drawings, 10 is an insui Specification of Letters Patent.

Patented April 6, 1909.

1906. Seal N0. 339,179.

lating base ot slate, soap-stone, or the like, upon which the switch mechanism is properly mounted. This switch is preferably of the double pole type so that in case the device is used with measuring instruments, the connection may be made with both ends the shunt of the instrument. The contacts are arranged in an arc of a circle, and are in pairs 11, 12, 18, etc., the conta-cts of each pair being in a vertical alinement and the pairs being sepa-rated by insulating material 14.

Y In the construction shown inthe drawings, tlie contacts are set into an insulating segment 15 so as to be Hush with vthe snrt'ace, and the ring is supported above the base 10 in any manner, as by the support 16. Electrical connection is made with these contacts by means oiz studs 17 and 18 which at the upper ends are screwed into the contact segments, and at their lower ends are provided with the necessary terminal connections 19.

und 21 so arranged as to be in the same plane with the contacts 11 and 12, respectively, and separated by strips of insulating material 22 and 23. These rings and insulating strips are mounted on a stud 24 as a Mounted concentrically with, `1 the ring 15 are-a pair of contact rings 20 center and supported by an insulating block 25. trolling arm 2G arrangedv to move between the insulating blocks 23 and 22. At the outer end ot' this arm is a pair of contact` brushes 2T and 28 adapted to bridge the pairs 'ot contacts 1.1 and 12 to the rings 20 and 21. 'Ihe end ot the arm passes between the rings and the segments, and the brushes mounted thereon slide over the contacts. In order to make a good connection between the Pivoted to this stud is a metallic con-V brushes and the contacts, I provide means for screwing the brushes intocontact. This means comprises an operating handle 29 which is mounted on the end of the arm 26, and which has screw connections with the brushes whereby the latter may be tightened on to the contacts by tui-ning the handle. The detail oflhis mechanism is shown in Fig. 4. The adjusting pin 30 which is rig idly screwed to the handle 29' is mounted on tliearni 26 by means of an insulating block 31, which is supported'at its middle by the arm. The brushes-27 and 28 are' set into the block and connected withithe adjusting pin` 'by right and left hand screw threads, the

brush 27 being insulated from the-stud by a bushing 32.

It will be seen that by turning the stud 3l by means of the handle 29, the brushes are screwed together, thereby tightening them into contact with the contact rings and segments. Electrical connection is made with the rings 2O and 2l in a manner similar to 4that of the segments l1 and 12, the studs 33 and 34 passing through. the base and screw-v ing at their upper ends into the rings. By this construction, it will be seen that the brushes 26 may be moved by means of the handle 29 so as to connect the rings .2O and 21 with the pairs of segments successively, and by turning the handle 29, the brushes may be screwed down so as .to make a good electrical connection with the contacts.

In Fig. 34A I have shown a slight modification in which the arm 35 carrying the con- `tacting brushes is situated above the fixed contacts, and the arm` itself is extended so as to form a pointer 36. In this form, the stud 37 instead of 4being provided with right and left hand screw threads is provided with a single thread 3S for the saine purpose, the spring 39 being provided to separate the brushes when the handle is turned.

Various other modifications of the construction may be made without departing from the spirit of my invention, the scope of which I have set forth in the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

l. A switch for electric circuits compris- `ing a series of contacts,v a movable element provided '.vith brushes adapted to engage said contacts, and means carried by the element and movable therewith for tightening the brushes into close relation with the contacts.

, 2. A switch for electric circuits comprising a' series of contacts, a pivoted controlling element adapted to successively engage said contacts, and means carried bythe element and movable therewith for tightening the same into close relation with the contacts.

means coi'itrolled by said handle for varying the pressure between the contacts and the n'iovable .element 3. A switch for electric circuits compris-? 6. A switch for electric circuits comprising a series of contacts arranged 1n an arc of a circle, a contact ring concentrlc there- -with, a movable element adapted to bridge the successive contacts and said ring, and means carried by the element and movable therewith for Varying the contacting pressure between the bridging element and the cont-acts. 7 A switch for electriccircuits comprising a series of contacts arranged in an4 arc of a circle, a circular contact arranged concentric therewith., a movable element pivoted concentric with said contacts and provided with a brush arranged to successively bridge the contacts andthe circular Contact, and means carried by the element. and movable therewith for varying the pressure between the contacts and the brush.

8. A switch for electric circuits comprising a series of pairs of contacts arranged in an arc of a circle, 'a pair of contact rings concentric therewith, a pivoted element adapted to bridge'said rings and said pairs of contacts successively, and means movable with said element for varying the contacting pressure between the bridging element and the contacts of each pair.

9. A switch for electric circuits comprising a series of pairs ofcontacts arranged in an arc of a circle, a pair of Contact rings concentric therewith,a pivoted elementA provided with a pair yof brushes movable between the rings and contacts and adapted to successively bridge the contacts of each pair and the rings, a handle for moving said element, and means whereby the contacting pressure of said brushes is varied by the turning of said handle.

10. A switch for electric circuits comprising concentrically arranged contacts, a pivoted element provided with a brush adapted to move in an arc of a circle between said contacts and engage the same,- and means 'carried by the element and movable therewith for tightening said brushes on to said contacts. p 1l. A switch for electric circuits comprising concentrically arranged contacts, a pivoted element provided with a brush adapted to move inl an arc of a circle between said contacts and engage the same, a handle for moving said. element, and screw connections between theA handle and the brush for vary- "ing the contacting pressure of theA latter.

12. A switch for electric circuits comprising concentrically arranged pairs of contacts a pivoted element provided with f. element, and screw connections etween the brushes adapted to move in an are of a. circle my .hand this nineteenth day of September,

between sald contacts and simultaneously 1906.

engage the pairs, a. handle for o erating the EDMUND B WEDMRE handle and the brushes for pressing the 1at- Witnesses: ter on to the contacts. CHARLES H. FULLER,

In witness whereof, I have hereuntol set J. A. FOSTER. 

